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    <title>API Overview</title>
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    Specifies Java packages for the programmatic, type safe handling of quantities
    and their expression as numbers of units. The core interfaces of this API are
    {@link org.unitsofmeasurement.unit.Unit} and {@link org.unitsofmeasurement.quantity.Quantity}.

    <h3>Definition of terms</h3>
    <p>This API adopts the definitions provided by the
    <a href="http://www.bipm.org/utils/common/documents/jcgm/JCGM_200_2012.pdf">International
    Vocabulary of Metrology</a> (VIM), with some adaptations:</p>
    <ul>
      <li><p><b>{@linkplain org.unitsofmeasurement.quantity.Quantity}:</b>
        property of a phenomenon, body, or substance, where the property has a magnitude
        that can be expressed as a {@linkplain java.lang.Number number} and a
        {@linkplain org.unitsofmeasurement.unit.Unit unit}.<br>
        <font size="-2">(Change compared to VIM: the term "reference" has been restricted to "unit")</font></p></li>

      <li><p><b>Kind of quantity:</b> aspect common to mutually comparable quantities.</p></li>

      <li><p><b>{@linkplain org.unitsofmeasurement.unit.Dimension}:</b>
        expression of the dependence of a {@linkplain org.unitsofmeasurement.unit.Unit unit} on the
        base units of a {@linkplain org.unitsofmeasurement.unit.SystemOfUnits system of units} as a
        {@linkplain org.unitsofmeasurement.unit.Dimension#getProductDimensions() product of powers
        of dimensions} corresponding to the base units, omitting any numerical factor.<br>
        <font size="-2">(Change compared to VIM: replaced "quantity" terms by "unit",
        because dimensions are associated to units in this API)</font></p></li>

      <li><p><b>{@linkplain org.unitsofmeasurement.quantity.Dimensionless}:</b>
        {@linkplain org.unitsofmeasurement.quantity.Quantity quantity} for which all exponents of
        the dimensions corresponding to the base units are zero.<br>
        <font size="-2">(Change compared to VIM: replaced "factors" terms by "dimensions")</font></p></li>

      <li><p><b>{@linkplain org.unitsofmeasurement.unit.Unit}:</b>
        real scalar {@linkplain org.unitsofmeasurement.quantity.Quantity quantity}, defined and adopted
        by convention, with which any other quantity of the same kind can be compared to express the
        ratio of the two quantities as a number.</p></li>

      <li><p><b>Base unit:</b>
        {@linkplain org.unitsofmeasurement.unit.Unit unit} in a conventionally chosen subset of a
        given {@linkplain org.unitsofmeasurement.unit.SystemOfUnits system of units}, where no
        subset unit can be expressed in terms of the others.<br>
        <font size="-2">(Change compared to VIM: replaced "quantity" terms by "unit",
        because dimensions are associated to units in this API)</font></p></li>

      <li><p><b>{@linkplain org.unitsofmeasurement.unit.SystemOfUnits System of units}:</b>
        set of base units and derived units, together with their multiples and submultiples,
        defined in accordance with given rules.<br>
        <font size="-2">(Change compared to VIM: omitted the reference to the
        <cite>system of quantities</cite>)</font></p></li>
    </ul>

    <h3>Links</h3>
    <ul>
      <li><a href="http://www.unitsofmeasurement.org">Units of Measurement</a> project home page</li>
      <li><a href="http://www.bipm.org/utils/common/documents/jcgm/JCGM_200_2012.pdf">International Vocabulary of Metrology</a> (VIM)</li>
    </ul>
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